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Presentation

Material Discovery and High Throughput Exploration of Ru Based Catalysts for Low Temperature Ammonia Decomposition

Katie McCullough Travis Williams Benjamin Ruiz Jochen Lauterbach

High throughput experimentation gives us the unique ability to generate massive, multidimensional datasets that are not typical for heterogeneous catalysis studies. Here, we show the synthesis and catalytic screening of over 100 different Ru based bimetallic catalyst combinations using 33 different metals that were synthesized via incipient wetness impregnation. The catalysts were analyzed using Wide Angle X-ray Scattering (WAXS) for phase identification. Catalysts were screened for ammonia decomposition activity using a 16-channel parallel plug flow reactor. Fourier transform infrared (FT-IR) imaging was used to analyze all 16 effluent streams in parallel in under one minute. All results obtained from WAXS…

Presentation

Development of a Highly Efficient COx-Free Ammonia Dehydrogenation System for Fuel Cell Applications

Young Suk Jo Junyoung Cha Hyuntae Sohn Suk Woo Nam Chang Won Yoon

The shortage of fossil fuels and emission of carbon dioxide to the environment have attracted an interest in discovering renewable energy as the next generation energy source. Owing to its intermittent and unpredictable nature, however, excess renewable energy needs to be stored and reused on demand. In the regard, hydrogen, which possesses a high gravimetric energy density and carbon free combustion process, has been extensively researched as a promising renewable energy carrier. However, the distribution and storage of hydrogen still raise important challenges due to the low volumetric energy density of hydrogen for its wide utilization. Currently, gaseous hydrogen transportation…

Article

Future Ammonia Technologies: Electrochemical (part 3)

Trevor Brown December 28, 2017

This series of articles on the future of ammonia synthesis began with a report on the NH3 Energy+ conference presentation by Grigorii Soloveichik, Program Director at the US Department of Energy's ARPA-E, who categorized the technologies as being either improvements on Haber-Bosch or electrochemical (with exceptions). ARPA-E invests in "transformational, high-risk, early-stage research," and recently began funding ammonia synthesis technologies, not to make renewable fertilizer but to produce "energy-dense zero-carbon liquid fuel." This article will introduce the six electrochemical technologies currently in development with funding from ARPA-E.

Presentation

Dense Metallic Membrane Reactor Synthesis of Ammonia at Moderate Conditions and Low Cost

Thomas F. Fuerst Sean Lundin Zhenyu Zhang Simona Liguori J. Douglas Way Colin A. Wolden

Commercial ammonia synthesis relies on the Haber–Bosch process that has remained largely unchanged for a hundred years. The equilibrium constant of this exothermic reaction quickly becomes unfavorable above 200 °C, but the catalyst requires temperatures above 400 °C to have sufficient activity. To overcome these conflicting requirements the process is conducted at extremely high pressure (100 – 200 atm) using multiple passes with inter-stage cooling to achieve sufficient conversion. A cost analysis reveals the compressors needed to reach the required pressures consist of 50% the capital cost for Haber-Bosch. Therefore, a longstanding scientific challenge has been to achieve NH3 synthesis…

Presentation

Nitride-Based Step Catalysis for Ammonia Synthesis at Atmospheric Pressure

Peter Pfromm Michael Heidlage Bin Liu Nannan Shan Viktor Chikan Hongfu Luo Nate Flesher

Formation of metal nitrides to activate dinitrogen is one avenue to ammonia and other nitrogen compounds. Attractive aspects are operation at atmospheric pressure and moderate temperatures, formation of stable chemical intermediates rather than reliance on somewhat sensitive heterogeneous catalysis, and inexpensive materials. If a single metal is used, however, one encounters tradeoffs somewhat akin to the well-known tradeoffs for Haber-Bosch catalysts. Results will be presented for metal nitride-based ammonia synthesis, and new metal alloys that can address some of the tradeoffs between affinity for nitrogen, and formation of ammonia when hydrogen is added. Options using water instead of hydrogen will…

Presentation

Exploring Peptide-Bound Catalysts for Electrochemical Ammonia Generation

Charles Loney Ashley Graybill Cheyan Xu Julie Renner Prashant Acharya David Suttmiller Lauren F. Greenlee Luke Wiles Katherine Ayers Wayne Gellett

Today, most ammonia (NH3) manufacturing occurs via the Haber-Bosch process. This process consumes hydrogen from fossil fuels, and as a result NH3 contributes the highest amount of greenhouse gas emissions out of the top 18 large-volume chemicals made globally. Because the process is high temperature (400°–500°C) and pressure (150–300 atm) with a low (15%) single-pass conversion efficiency, the plants have to be very large to be economical. This means that ammonia is shipped from centralized locations, further increasing greenhouse gas emissions because of the fuel consumed in transportation. Additionally, their large size makes it difficult to integrate with renewable sources…

Presentation

LiH Mediated Ammonia Synthesis Under Mild Condition

Jianping Guo Ping Chen

Having a hydrogen content of 17.6 wt% NH3 is an attractive hydrogen carrier. The key issue for NH3 synthesis and decomposition is the development of non-noble metal based, highly active and stable catalysts that can be operated under mild condition. With the understanding on the interaction of LiH and Li2NH with 3d metals or their nitrides, novel catalyst systems, i. e., LiH-3d transition metals for NH3 synthesis and Li2NH-3d transition metal for NH3 decomposition, that have activities surpassing the highly active Ru-based catalysts were developed. The unique chemistry among TM, Li, N and H creates a two-reactive center mediated pathway…

Presentation

Influence of H2 / N2 Ratio on Dynamic Behavior of Ammonia Production on Ru Catalyst Under Low Pressure Condition

Hideyuki Matsumoto Javaid Rahat Tetsuya Nanba

Recently deployment of renewable energy such as sunlight and wind power or deployment of process technologies for carbon dioxide capture and storage (CCS) is indispensable to reduce the CO2-emission. However, there are some issues to be solved in order to accelerate the mass deployment of renewable energy. Since amount of renewable energy quite changes unstably with time, which depends on weather and place, development of process systems technology is an issue for stable and effective utilization of electric power that is generated by fluctuating renewable energy. Those in national institute of National Institute of Advanced Industrial Science and Technology (AIST)…

Presentation

Early Transition Metal Carbide and Nitride Supported Catalysts for Ammonia Synthesis

Zixuan Wang Levi T. Thompson

More than 180 million tons of NH3 are produced annual via the Haber-Bosch process which converts N2 and H2 at high temperatures (400 – 500°C) and pressures (150 – 300 bars). Ammonia synthesis also accounts for 1-2% of global energy consumption.1 The development of higher activity catalysts that can operate under less severe conditions would enhance the economics associated with and sustainability of NH3 synthesis. Research described in this paper investigates the performance of transition metal carbide and nitride supported metals for NH3 synthesis. Previously, Mo2C and Mo2N have been reported to be more active than Ru-based catalysts, but slightly…

Presentation

Design of Iron-Nickel Nanocatalysts for Low-Temperature Electrochemical Ammonia Generation

Lauren F. Greenlee Shelby Foster Prashant Acharya David Suttmiller Charles Loney Julie Renner Wayne Gellett Katherine Ayers

The Haber-Bosch industrial process for ammonia production is the cornerstone of modern commercial-fertilizer-based agriculture. Haber-Bosch ammonia fueled the global population growth of the 20th century, and approximately half of the nitrogen in human bodies today originates from ammonia-based fertilizer produced by the Haber-Bosch process. However, the Haber-Bosch process operates at high temperature and high pressure to achieve high conversion efficiencies, and the hydrogen input comes from steam reforming of coal or natural gas. In addition to the energy costs, the large production of carbon dioxide as a greenhouse gas and the large required economies of scale motivate research efforts to…